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Investigation on the penetration of jacketed rods with striking velocities of 0.9-3.3 km/s into semi-infinite targets

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Defence Technology（防务技术） 2022年第3期18卷 476-489页

作者： Kui Tang Jin-xiang Wang Hai-ping Song nan zhou National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing210094China China North Vehicle Research Institute Beijing100072China Department of Criminal Science and Technology Nanjing Forest Police CollegeNanjing210023China

In this study, a combined experimental, numerical and theoretical investigation is conducted on the penetration of semi-infinite 4340 steel targets by a homogeneous 93 W rod and two types of jacketed rods with striking velocities of 0.9-3.3 km/s. The results show that the jacketed rods produced typical“co-erosion” damage at all test velocities, except for the 93 W/1060 Al jacketed rod, which switched from an early “bi-erosion” damage to later “co-erosion” damage at a striking velocity of 936 m/s. However, the homogeneous 93 W rod always forms a large mushroom head during the penetration process. The damage mechanisms of these two types of jacketed rods differ for striking velocities of 0.9-2.0 km/s, but this difference gradually decreases with increased striking velocity. For velocities of 2.0-3.3 km/s, all three types of projectiles exhibit typical hydrodynamic penetration characteristics, and the damage mechanisms of the two types of jacketed rods are almost identical. For the same initial kinetic energy, the penetration performance of the jacketed rods is distinctly superior to that of the homogeneous 93 W *** with jacket density, jacket strength shows a more significant influence on the damage mechanism and penetration performance of the jacketed rod. Finally, an existing theoretical prediction model of the penetration depth of jacketed rods on semi-infinite targets in the co-erosion mode is modified. It transpires that-in terms of penetration depth-the modified theoretical model is in good agreement with the experimental and numerical observations for 93 W/TC4 and 93 W/1060 Al jacketed rods penetrating semi-infinite 4340 steel targets.

关键词： Jacketed rod Semi-infinite target Damage mechanism Penetration performance

BMI与血脂异常患病关联强度剂量-反应关系研究

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中国卫生统计 2024年第1期41卷 18-22页

作者：杜金玲周楠陈一佳宋莹倩王巍巍洪忻南京医科大学附属南京疾病预防控制中心慢性非传染病防制科 210003 南京医科大学公共卫生学院流行病与卫生统计学系

目的采用限制性立方样条模型探讨BMI与血脂异常患病关联强度的剂量-反应关系。方法 2017-2018年开展南京市慢性病防控社会因素调查,对61098名18岁及以上常住居民进行问卷调查、身体测量以及实验室检测。采用复杂抽样基于设计的logisti... 详细信息

目的采用限制性立方样条模型探讨BMI与血脂异常患病关联强度的剂量-反应关系。方法 2017-2018年开展南京市慢性病防控社会因素调查,对61098名18岁及以上常住居民进行问卷调查、身体测量以及实验室检测。采用复杂抽样基于设计的logistic回归模型和限制性立方样条模型分析BMI与血脂异常患病的关联强度及剂量-反应关系。结果最终纳入60283名调查对象。血脂异常患者17093例,加权患病率为29.8%。多因素logistic回归调整混杂因素后,超重人群患血脂异常的风险是体重正常人群的1.43倍(95%CI:1.36~1.49),肥胖人群患血脂异常的风险是体重正常人群的1.97倍(95%CI:1.83~2.12)。限制性立方样条模型结果表明,女性、青年人以及中老年人群,其BMI与血脂异常患病风险均呈非线性剂量-反应关系;男性BMI与血脂异常患病风险呈线性剂量-反应关系。结论控制体重对预防血脂异常有十分重要的作用。

关键词：限制性立方样条血脂异常体质指数

High thermal stability and blue-violet emitting phosphor CaYA1O4:Ti^4+with enhanced emission by Ca^2+vacancies

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Journal of Rare Earths 2020年第3期38卷 227-233页

作者： Mao Xia Yongli Zhang Minghui Li Yuan Zhong Simin Gu nan zhou Zhi zhou College of Science Hunan Agricultural UniversityChangsha 410128China Hunan Optical Agriculture Engineering Technology Research Center Changsha 410128China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Blue-violet light can not only enhance the total content of biomass and glucoside but also enrich the taste of the ***,it is meaningful to study the blue-violet luminescent materials for plant *** this study,titanium(IV)-activated CaYAlO4(CYAO) phosphors were synthesized by conventional hightemperature solid-state reaction.X-ray powder diffraction was employed to analyze the crystalstructure of *** is found that the doped Ti^4+ ions do not change obviously the crystal structure of *** 246 nm excitation,CaYAl1-xO4:xTi^4+phosphors exhibit broad blue-violet emission band peaking at 395 nm,which can be attributed to the charge transfer of Ti^4+-O^2-.Moreover,this phosphor exhibits strong thermal *** luminescence emission intensity at 150℃maintained about 91 mol% of its initial value at room ***,the electron transition process and concentration quenching mechanism of CaYAl1-xO4:xTi^4+are discussed in *** excellent luminescent properties indicate that CaYAl1-xO4:xTi^4+phosphor may have promising application in indoor plant cultivation.

关键词： Blue-violet-emitting Ca^2+ vacancies Phosphors Plant growth lighting Ti^4+-activated

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电子温控辊形描述方法及其特征调控规律

塑性工程学报 2024年第8期31卷 199-207页

作者：许志强陈启发白宇航海杨周昊男燕山大学机械工程学院河北秦皇岛066004 燕山大学国家冷轧板带装备及工艺工程技术研究中心河北秦皇岛066004

从辊形电子温控技术原理及电子温控辊形构成特点出发,选取3种典型多项式拟合模型对局部辊形进行了拟合分析,确立了辊形描述基础模型;提出了两种辊形有效影响区边界评价方法,分析了辊形描述方法在不同电流参数及温控片长度参数下的普遍... 详细信息

从辊形电子温控技术原理及电子温控辊形构成特点出发,选取3种典型多项式拟合模型对局部辊形进行了拟合分析,确立了辊形描述基础模型;提出了两种辊形有效影响区边界评价方法,分析了辊形描述方法在不同电流参数及温控片长度参数下的普遍适应性;以提升预设效率为目的,采用切比雪夫多项式对辊形曲线进行划分,以特征分量作为技术应用中的预设辊形调控量,探究了调控参数对辊形曲线参数化的影响。结果表明,拟合模型阶次越高,拟合效果越好,但提升效果随阶次增高而减弱。不同有效辊形区域评价标准下,比例边界相较于定值边界表现出更稳定的评价表现,更适用于电子温控技术。以辊形二次凸度及四次凸度作为预设调控量可高效表述局部辊形,电流参数对二次凸度更具调控力,温控片长度二次凸度及四次凸度具有相似调控力。研究提供了一种电子温控辊辊形预设参量评价标准。

关键词：辊形曲线辊形电子温控技术 TEC 凸度

节约体能法对宫颈癌同步放化疗病人癌因性疲乏的干预效果

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护理研究 2024年第2期38卷 258-266页

作者：芦沁蕊焦培娟周楠智诗涵顾炜西安交通大学第一附属医院陕西710061 西安交通大学医学部新疆医科大学护理学院

目的:探讨节约体能法对宫颈癌同步放化疗病人癌因性疲乏(CRF)的干预效果。方法:采用方便抽样法,选取2018年4月—12月在西安交通大学第一附属医院放疗病区住院治疗的108例宫颈癌病人作为研究对象,按入院时间分为对照组和干预组,每组54例... 详细信息

目的:探讨节约体能法对宫颈癌同步放化疗病人癌因性疲乏(CRF)的干预效果。方法:采用方便抽样法,选取2018年4月—12月在西安交通大学第一附属医院放疗病区住院治疗的108例宫颈癌病人作为研究对象,按入院时间分为对照组和干预组,每组54例。对照组给予放疗科常规护理,干预组在放疗科常规护理基础上给予节约体能法的干预。于治疗开始前、放疗5次结束、放疗10次结束、放疗15次结束、放疗20次结束及放疗25次结束后采用中文版Piper疲乏修订量表(RPFS)对病人CRF严重程度进行评价。结果:干预期间对照组流失3例病人,干预组流失4例病人,最终对照组51例病人完成研究,干预组50例病人完成研究。中文版RPFS总分及行为疲乏、情感疲乏、感知疲乏、认知疲乏维度得分的干预主效应、时间主效应均有统计学意义(P0.05)。在放疗10次结束、放疗15次结束、放疗20次结束及放疗25次结束4个时间点,对照组与干预组的中文版RPFS总分及各维度得分差异有统计学意义(P<0.05)。结论:宫颈癌同步放化疗病人CRF水平在治疗期间升高,节约体能法可有效降低各时间点宫颈癌同步放化疗病人的CRF水平。

关键词：宫颈癌癌因性疲乏(CRF) 节约体能法放疗化疗护理

Deformation and Failure Analysis of River Levee Induced by Coal Mining and Its Influence Factor

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Computer Modeling in Engineering & Sciences 2017年第2期113卷 183-194页

作者： Meng Li Jixiong Zhang nan zhou Qiang Zhang State Key Laboratory of Coal Resources and Safe Mining School of MinesChina University of Mining&TechnologyXuzhou221116China

To study the influence of coal mining on the stability of river levees,a mechanical model of mining-induced river levee deformation was *** was based on the mining-induced deformation characteristics of river levees and the application of a typical surface subsidence ***,a failure criterion was proposed for river *** some examples,the deformation of,and stress distribution through,river levees under the influence of mining were obtained:the maximum tensile stress on the bottom of the river levee was less than the tensile strength,under which circumstance the river levee remained ***,this research analyzed the influence of three factors including the maximum surface subsidence wmax,half-length of surface subsidence basin L,and foundation coefficient k on the stability of river *** showed that reducing the mining height of the working face and the foundation co-efficient,and increasing the strike length of the working face could reduce the influence of mining on river *** results provided a theoretical basis for predicting the mining-induced deformation and failure of river levees.

关键词： Mining river levee surface subsidence mechanical model Winkler foundation beam

Improving the electrocatalytic activity of Fe,N co-doped biochar for polysulfide by regulation of N-C and Fe-N-C electronic configurations

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International Journal of Minerals,Metallurgy and Materials 2023年第12期30卷 2421-2431页

作者： Jingchun Sun Jindiao Guan Suqing zhou Jiewei Ouyang nan zhou Chunxia Ding Mei’e Zhong School of Chemistry and Materials Science Hunan Agricultural UniversityChangsha 410128China Hunan Engineering Research Center for Biochar Hunan Agricultural UniversityChangsha 410128China

The conversion of agricultural residual biomass into biochar as a sulfur host material for Li-S batteries is a promising approach to alleviate the greenhouse effect and realize waste resource ***,the large-scale application of pristine biochar is hindered by its low electrical conductivity and limited electrocatalytic *** paper addressed these challenges via the construction of Fe-N co-doped biochar(Fe-NOPC)through the copyrolysis of sesame seeds shell and ferric sodium ethylenediaminetetraacetic acid(NaFeEDTA).During the synthesis process,NaFeEDTA was used as an extra carbon resource to regulate the chemical environment of N doping,which resulted in the production of high contents of graphitic,pyridinic,and pyrrolic N and Fe-Nx *** the resulting Fe-NOPC was used as a sulfur host,the pyridinic and pyrrolic N would adjust the surface electron structure of biochar to accelerate the electron/ion transport,and the electropositive graphitic N could be combined with sulfur-related species via electrostatic ***-Nx could also promote the redox reaction of lithium polysulfides due to the strong Li-N and S-Fe *** from these advantages,the resultant Fe-NOPC/S cathode with a sulfur loading of 3.8 mg·cm^(-2)delivered an areal capacity of 4.45 mAh·cm^(-2)at 0.1C and retained a capacity of 3.45 mAh·cm^(-2)at ***,this cathode material holds enormous potential for achieving energy-dense Li-S batteries.

关键词： sesame seeds shell copyrolysis biochar Fe-N co-doping Li-S batteries

Degradation and detoxification of microcystin-LR in drinking water by sequential use of UV and ozone

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Journal of Environmental Sciences 2010年第12期22卷 1897-1902页

作者： Xiaowei Liu Zhonglin Chen nan zhou Jimin Shen Miaomiao Ye State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology Harbin 150090 China Beijing General Municipal Engineering Design & Research Institute Beijing 100082 China

Microcystins （MCs） produced by cyanobacteria are strong hepatotoxins and classified as possible carcinogens. MCs pose a considerable threat to human health through tainted drinking and surface waters. Herein filtrated water from a waterworks in Harbin, China, was spiked with microcysfin-LR （MC-LR） extracted from a toxic scum of microcystis aeruginosa, and the spiked sample waters were treated using UV irradiation with consequent ozonation process （UV/O3）, compared with ozonation at a dose range commonly applied in water treatment plants, UV irradiation at 254 nm and UV irradiation combined with ozonation （UV＋O3）, respectively. The remaining of toxins were analyzed using high-performance liquid chromatography and also determined using a protein phosphatase type 2A inhibition assay, which was utilized to evaluate the reduction in toxicity. Results indicated that in comparison to other three processes （O3, UV, and UV＋O3）, UV/O3 process could effectively decrease both the concentration and toxicity of MC-LR at 100 μg/L level after 5 min UV irradiation with consequent 5 min ozonation at 0.2 mg/L （below 1 μg/L ）, while 0.5 mg/L ozone dose was required for the level below 0.1 μg/L. The addition of an UV treatment step to the existing treatment train may induce significant transformation of micropollutants and breaks down the natural organic matters into moieties unfavorable for ozone decomposition, stabilizing the ozone residual. These findings suggested that sequential use of UV and ozone may be a suitable method for the removal of these potentially hazardous microcystins from drinking water.

关键词： microcystins ozonation UV irradiation toxicity protein phosphatase type 2A inhibition assay

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大学生创新素养测评体系构建及应用研究

青岛科技大学学报(社会科学版) 2024年第03期40卷 71-79页

作者：周南南王子铭孙慧桐纪文卿青岛科技大学经济与管理学院

以既有教育理论成果为基础，结合教学实践，围绕大学生的学习能力、学术能力、创新能力及实践能力四大核心能力，构建大学生创新素养测评体系，对大学生创新素养水平进行测算。研究结果表明：大学生创新素养总体表现良好，学习能力优异... 详细信息

以既有教育理论成果为基础，结合教学实践，围绕大学生的学习能力、学术能力、创新能力及实践能力四大核心能力，构建大学生创新素养测评体系，对大学生创新素养水平进行测算。研究结果表明：大学生创新素养总体表现良好，学习能力优异，但创新能力有待提高；交叉学科大学生的综合得分最高，自然学科和社会学科大学生的综合得分次之；本科生在学习能力上的表现优于研究生，研究生在学术能力和实践能力上的表现优于本科生；不同院校层次的大学生在学习能力、学术能力、创新能力和实践能力四个维度上的得分存在明显差异。因此，结合大学生创新素养测评结果，为不同学科类别、学历层次、院校层次的大学生提供有针对性的方案，分别提升大学生的四大核心能力，可有效提升大学生创新素养水平。

关键词：大学生创新素养学习能力学术能力创新能力实践能力